Toamasina [toˈmasinə̥], meaning "like salt" or "salty", unofficially and in French also Tamatave, is a city (commune urbaine) on the east coast of Madagascar on the Indian Ocean. The city is the chief seaport of the country, situated 215 km (134 mi) northeast of its capital and biggest city Antananarivo, near the centre of the eastern coast at 18 10 S, 49 32 E. According to the 2001 census, Toamasina had population of 179,045. The city is served by Toamasina Airport.

Toamasina is the capital of Atsinanana region. Gervais Rakotomanana is the president of the city by special delegation since 30 May 2007. The former mayor, Roland Ratsiraka, was suspended after a decision in the municipal council in early 2007.

Toamasina owes its importance to the existence of a coral reef which forms a spacious and fairly commodious harbour, entered by two openings. The city center is built on a sandy peninsula which projects at right angles from the general coastline. On this are crowded together a considerable number of houses, with shops and merchant offices located in the main thoroughfares.